Conventional modular switch architectures relied on the use of a supervisor module coupled to one or more port termination modules (i.e., “line cards”) through specialized (and often proprietary) backplane circuitry. Because each modular switch typically required its own supervisor module, network expansion that required additional switches also increased the number of supervisor modules. The increase in number of supervisor modules resulted in a corresponding increase in network complexity and overhead.
In an effort to contain the growth of management modules (and corresponding network management overhead) in a particular network segment, solutions for distributing or “extending” line card functionality were developed. Conventional line card functionality was moved from the modular switch (coupled to a dedicated to supervisor module) to a standalone enclosure that could be remotely connected back to a supervisor module over standard Ethernet. Using these “port-extended” architectures, network expansion to a remote location no longer required a complete modular switch (with a dedicated supervisor module and line card modules). Instead, one or more less expensive standalone line card modules could be installed and configured for control by an existing supervisor module.
In the port-extended data plane architecture, switching is generally performed on the supervisor module. Frames received on satellite host (i.e. port termination module) ports may be sent over a “fabric link” to the controller where they are switched. For correct packet switching, the supervisor module should, in the inbound direction, know the host port on which the packet arrived (or, in the outbound direction, must specify the host port on which the packet should leave). An Ethernet technology known as “vnTag” (i.e., virtual NIC tag) addresses this issue. Each satellite host port is assigned an identifier known as a “vif_id.” Once a fabric link is brought up by SDP (Satellite Discovery Protocol) and put into use, each frame transiting a fabric link includes a “vnTag” header that contains fields for “src vif_id” (SVIF) and “dst vif_id” (DVIF).
The presently disclosed systems and methods for designating packets for customized data processing in port-extended architectures are directed to overcoming one or more of the problems set forth above and/or other problems in the art.